Question

The average lifespan of an earthworm is-
A) 13-15 years
B) 28-30 years
C) 6-9 years
D) 24-28 years

Answer 1

Hint: An earthworm belongs to the phylum Annelida. It is a terrestrial invertebrate that belongs to the order Opisthopora. They possess a tube-within-a-tube body plan and are externally segmented with corresponding internal segmentation with setae present on all segments.

Complete answer:
The average lifespan of an earthworm is 6-9 years.
Key points regarding Earthworms are-
• Earthworms occur worldwide where soil, water, and temperature are favorable.
• Earthworms are commonly found in the soil feeding on a wide variety of organic matter.
• The average life span is 6-9 years.
• The organic matter includes plant matter, rotifers, nematodes, bacteria, fungi, and other microbes.
• An earthworm's digestive system runs along the length of its body.
• It respires through its skin which is moist.
• It has a double transport system that moves within the fluid-filled coelom and a primitive, closed circulatory system.
• It possesses a central and peripheral nervous system.
• Large numbers of chemoreceptors are present near its mouth.
• Earthworms are hermaphrodite. The term hermaphrodite means that they possess both male and female in the same organism or in the same body.
• They lack a true skeleton but maintain their structure that functions as a hydrostatic skeleton.

So, the correct option is (C).

Additional information: Earthworms are biologically important as they aerate the soil. They are also known as Farmer’s best friend as they have importance in soil fertility.

Note:
An earthworm is a common name for the largest members of Oligochaeta.
Previously, they were in the order Opisthopora because the male pores opened posterior to the female pores.
Large worms are termed as Megadriles while small are termed as microdriles.